But are.

"Mean Girls" taught us that Halloween was the only time of the year when wearing underwear in public was acceptable. Sexy costume options were limited to the role-playing bedroom-type things: cops, nurses, Playboy Bunny.

Then it evolved — or devolved, depending on how you look at it — into a race for the most current and the funniest, like last year's hit Sexy Pizza Rat from lingerie and costume site yandy.com.

"We always try to stay topical and front of mind," Yandy spokeswoman Sarah Chamberlain said. "We find that, especially over the last few years, that those do the best for us. Our bread and butter is the sexy costumes."

This year's play at the most topical and funny? Yandy’s Sexy Undecided Voter. That’s right, there’s a sexy costume in likeness of Ken Bone the guy who became famous for wearing a red sweater and asking a question at the second presidential debate. And the demand is clearly there — sexy Ken Bone sold out within hours of being posted to the site.

"We weren’t expecting that at all," Chamberlain said. "We just thought it would be funny to get it up on the site quickly. It was a lot bigger of a costume than we were anticipating."

Don’t worry: He’s back in stock on yandy.com. The price? $95.95. Chamberlain attributes that to the high-quality materials and quick turnaround.

"We're able to manufacture them really quickly," she said. "They're not a typical bag costume that you find at your Halloween store."

Generally speaking, the smaller or more topical the costume, the higher the price. And online shops like halloweencostumes.com have no problem selling sexy costumes.

"The biggest thing with sexy costumes is that the demand is high," halloweencostumes.com marketing manager Leigh Wendinger said. "We always like to bring some humor."

But you came here to look at this year's most ridiculous sexy costumes, not to learn facts about things. So let's get on with it:

1. Sexy taco

You know, it really wasn't all that sexy until they added a scandalous and revealing sombrero. No, but seriously. Everyone loves tacos. This is brilliant. (It's also a popular one. There's only one left.) ($59.99.)

Hard or soft?(Photo: halloweencostumes.com)

2. Sexy poop emoji

Sexy is combining two great things, right? Poop and a way to communicate through pictures without all that pesky talking. All in one neat little brown glorified leotard package! ($57.95.)

IndyStar News Director Alvie Lindsay contributed to the Hamburglar joke on this report. Call Amy Bartner, who is dressing up as Sexy Weird Al for Halloween, at (317) 444-6752 and follow her on Facebook, Twitter, and Instagram.